System of control



A. H. CANDE4E.

SYSTEM OF CONTROL.

APPLICATION FILED OCT. 6. I919.

1,427,856, Pit6ilt8d Allg-29,1922.

750/1 F! .1 lg j j; a A?! 9 g y 10 II i F] i 2 Ground F3 Ground f ofSm'fc/Jes WI TNESSES: I INVENTOR Andrew/z Candee 3 7ATTO'RNEY T 0 all whom it may concern:

UNITED STATES,

PATENT OFFICE.

HOUSE nrnotenrc VANIA.

8i: MANUFACTURING- GOMPANY, A CORPORATION OF PENNSYL- SYSTEM OF CONTROL.

Specification of Letters Patent. Patente'd' Aug. 29, 1922.

Application filed October 6, 1919. Serial No. 328,842.

Be it known that I, ANDREW H.0ANDEE, a citizen of theUnitedStates, and a resident of Pittsburgh, in thecounty of Allegheny and State of Pennsylvania, have invented a newand useful Improvement in Systems of Control, of which the following is aspecificatiou I .My invention relates to systemsof control for dynamo-electric machines, and it has particular relation to main-circuit connec tions for a two-motor railway equipment,

- or the like.

. One object of my invention toprovide a relatlvely simple and inexpensive system i of connections whereby uniform operation of sistor that is connected intermediate two driving motorsand is-excluded from circuit 111 unequal steps during series COIIIIGCtlOIi of the motors, whereas, under parallel operating conditions of the motors, the unequal sections of the resistor are connected in parallel relation and the connection 01": the resistorto the supply circuit is such as to insure equal voltages'upon the two motors in their initial parallel-circuit relation.

My invention may bestbe understood by a reference to the wherein s 1 Figurel is adiagrammatic vlew of the accompanying drawing,

main circuits of a system of control organ ized' in accordance with my present inven tion;and i Fig.2 is a simplifieddiagrammatic View ofan auxiliary controlling system for operating the various switches in the preferred order that is indicated'ln the sequence chart,

Fig. 3, of well-known form.

1 Referring to'Figll, the system here shown comprises suitable supply-circuit conductors Trolley and Ground; a plurality of driving motors respectively having commutator-type'armatures A1 and A2 and series field windings F1 and F2; an accelerating "resistor 1 having unequal portions 1a and -1b;* and a plurality of governing switches for the motors: a line switch LS1 for series operation a second line switch LS2 for parallel operation, another parallel-connect- 1 Fig. 3;

ing switch G and two resistor shortcirouiting switches R1 and R2. I

The switch R1 is connected across the larger section 1a of the accelerating resistor 1, while the switch R2 is connected across the terminals of the entire resistor. The switch LS2 connects the Trolley to the junctionpoint of the resistor sections 10,

and 1?). Switch LS1 serves to connect-the trolley with the left-hand terminal of the motor having the armature A1, while switch G is connected between the same terminal and Ground. p

In Fig. 2, I have shownva simple master controller for directingenergy from a battery B, or other suitablesource, to the actuating coils of the respective switches in the preferred. order, as indicated in Assuming that it is desired to effect ac- ,celeration of the motors, the master controller MC is actuated to its initial opera tive position a whereupon a circuitis es- 'tablished from one terminal of the battery B, through conductor 2, control fingers 3 and 4:, which .are bridged by contact seg- 'ment 5 of the master controller, conductor 6, the actuating coil. of line switch'LSl and conductor 6a'to the negative battery terminal. The line switch LS1 is thus closed, as indicated in step a oi; the sequence chart.

Under such conditions, amain circuit is established from the trolley through conduct-or 7, line switch LS1, junction-point- 8,conductor 9, field winding F1, armature "A1, junction point 10. the entire accelerating resistor 1, junction-point l1, armature A2 and field winding F2 to Ground. The

driving motors are thus connected in seriesrelat1on,withthe acceleratlng resistor 1 located between them, across the supply circuit.'

Movement of the" master controller to position 6 effects en'gagement of thev contact segment 5 with" control finger 1'2,

whence circuit is completed through conductor 13 and the 'actuating'coil' of the switch R1 to the negative conductor 6d. The larger resistor section 1a is thus short-circuited to effect a predetermined degreeof acceleration of the driving'motors.

In position 0 of the master controller, a new circuit is established from the contact segment 5 through control finger 15, con-1- ductor 16 and the actuating coil of the switch R2. The remaining or smaller resistor section 16 is thusalso excluded from circuit although, as previously stated, the switch R2 is connected across the entire resistor 1.

To effect transition of the motors from series to parallel relation, the master controller is moved to position (Z, whereupon, at first, control finger l2 breaks contact with controller segment 5, to cause the switch R1 to open. A circuit is next established from the contact segment 5, through control finger 17 and conductor 18 to the actuating coil of the line switch LS2, and subsequently the control finger 4; becomes disengaged from the contact segment 5 to effect opening of the line switch LS1. Just before the master controller reaches its position (Z, a new circuit is established from the contact segment 5 through control finger 20 and conductor 21 to the actuating coil of the switch Gr.

Consequently, in the first parallel position (Z of the master controller, the main circuits may be traced as follows: from the trolley through conductor 19, line switch LS2, junction-point 14- of the resistor sections 1a and 1b, where the circuit divides and passes through parallel circuits including the two resistor sections and the switch R2. One circuit is continued from the junc mains closed during transition and parallel operation of the motors, it follows that the amount of resistance inserted in circuit with each of the motors is the same, even though the resistor sections 1c and 1?) are unequal, which is desirable for purposes of series acceleration.

Furthermore, the line switch LS2 need not be connected to the junction-point 1 but may be joined to any desired point in the resistor 1, whereby the effective resistance in circuit with the parallel-related motors may be varied as desired.

In position 6, contact segment 5 again enfiages control finger 12, whereby the switch 1 is once more closed to complete the shorteircu-it of the resistor l and thus accelerate the motors to full-parallel relation.

It will be understood that the principles of my invention, whereby unequal resistance steps may be employed during series opera tion of the motors and equal resistance values are included in circuit with the motors during parallel. acceleration, may be readily applied to systems involving the use of more than two resistor short-circuiting switches.

in this way, the proper proportioning of the resistance steps for smooth acceleration during both series and parallel connection of the motors may be provided.

I do not wish to be restricted to the specific circuit connections or arrangement of parts herein set forth, as various modifications thereof may be made without departing from the spirit and scope of my invention. 1 desire, therefore, that only such limitations shall be imposed upon my invention as are indicated in the appended claims.

1 claim as my invention:

1. In a system of control, the combination with a plurality of dynamo-electric machines and an accelerating resistor, of means comprising five switches for effecting seriesparallel operation of the machines including unequal exclusions of resistor sections during series operation and equal distribution of the resistor in the motor circuits for parallel operation.

2. In a system of control, the combination with a plurality of dynamo-electric machines and an accelerating resistor permanently connected between them, of switching means for producing unequal resistance steps dun ing series operation and equal voltage distribution for parallel operation.

3. In a system of control, the combination with a plurality of dynamo-electric machines and an accelerating resistor permanently connected between them, of two individual switching means respectively adapted to be connected across a part and the whole of said resistor, and a line switch adapted to be connected to an intermediate point of the resistor.

4. In a system of control, the combination with a plurality of dynamo-electr c machines and an accelerating resistor ermanently connected between them, a switc 1 adapted to be connected across a section of said resistor. a second switch adapted to be connected. across the whole of the resistor, and a line switch adapted to be connected to an intermediate point of the resistor, said second switch and said line switch being closed during parallel operation of the motors.

5. In a system of control, the combination with a plurality of dynamo-electric machines and an accelerating resistor permanently connected between them, of a switch for short-circuiting a major portion of said resistor and a second switch for subsequently short-circuiting the whole resistor during series operation of the motors, and a line switch connected to an intermediate point of said resistor during parallel operation of the motors, said second switch remaining closed during transition and parallel operation of the motors to balance the voltages applied thereto.

6. The method of operating a plurality of motors in conjunction. with a supply circuit and an accelerating resistor which consists in excluding said resistor from circuit in unequal steps during series operation of the motors, and parallel-circuiting the resistor to produce equal voltage distribution from the supply circuit to the motors during parallel operation thereof.

7 The method of operating a plurality of motors in conjunction with a supply circuit 10 and an accelerating resistor which consists in excluding said resistor from circuit in unequal steps during series operation of the motors, and connecting a supplycircuit conductor to an intermediate point of said resistor and joining the ends thereof during parallel operation of the motors.

In testimony whereof, I have hereunto subscribed my name this 30th day of Sept. 1919.

ANDREW H. CANDEE. 

